1. Area of the Art
The present invention is in the field of cellular telephonic communication and more specifically to a system for ensuring safe use of cellular telephones while driving.
2. Description of the Background of the Invention
Within the last fifteen years, the cellular telephone (cell phone) has evolved from a bulky, expensive device that was rarely seen to an inexpensive, tiny device of ubiquitous presence. One has only to walk through a shopping mall to see that virtually every person from sub-teenagers to octogenarians is talking on a cell phone. In a mall this causes minor inconveniences as the telephone users pay more attention to their conversations than to their walking and collide with each other or with stationary objects. Unfortunately, the same pattern is repeated in automobiles. Almost every car has a cell phone, and conversing drivers often lose track of their driving as they communicate. Although there was some thought that the lack of “hands-free” telephones exacerbated the problem, this supposition has proven untrue. The most up to date studies have shown that use of cellular telephones while driving increases the frequency and severity of accidents to about the same degree whether or not a hands-free phone is used. Thus, the dangers of one handed driving and of looking at the phone buttons rather than the road are secondary to the serious inattention caused by talking on the phone while driving. Many states and municipalities are attempting to deal with this problem by passing laws against “driving while phoning” but these laws are, at best, difficult to enforce.
The cellular telephone system is a technological wonder, and a number of driving-related enhancements to that system have been proposed. WO 96/01531 uses the cellular telephone system to determine the location and speed of a vehicle carrying an active cellular telephone. It is proposed that this system be used for an automatic parking system (to record the presence of a vehicle in a parking slot & charge for that parking, etc.), as a speed radar system that could automatically charge speeding violations to a user's telephone bill or as a theft deterrent to locate stolen vehicles. WO 98/16077, WO 98/25158 and WO 98/59256 disclose the use of a GPS (Global Positioning System) receiver in conjunction with the cellular network to derive similar information. Unfortunately, pure GPS systems have inadequate response times for most safety uses.
Japanese laid-open patent application H10-42371 deals with another aspect of the driving while phoning problem. That application discloses a vehicle mounted unit that jams any cellular signals while the car is in operation. Of course, this makes the reception of important calls impossible. U.S. Pat. No. 6,262,657 to Okuda et al. obviates some of these problems by automatically issuing a driver alert (received over the telephone) when driving characteristics become erratic while a cellular phone is being used. However, both of these solutions require a separate unit mounted in the vehicle. Thus, a user is not protected in rental cars or cars other than his or her usual vehicle.
An independent development in the arena of driving safety is the camera equipped road intersection. The traffic light or signal is mainstay of urban and suburban traffic control. Intersections in most well-traveled areas are controlled by traffic signals. These devices are largely responsible for bringing some semblance of order to traffic flow by periodically stopping the traffic on one route to allow traffic on an intersecting or crossing route to traverse an intersection. The change of signals from yellow and then to red should ensure orderly and safe traffic flow. Unfortunately, there are at least two problems: lack of driver attention (often exacerbated by cell phone use) and drivers attempting to beat the system. Lack of attention can arise from numerous causes including use of a cellular telephone. The urge to “beat the system” is to some extent a byproduct of the signal system itself. The change from green to yellow is made to allow prudent drivers to stop safely before they enter the intersection. Because the signal in the crossing direction remains red during the yellow portion of the cycle, cars caught in the intersection have a chance to safely exit before cross traffic begins to flow. The problem is that drivers soon learn that it is “legal” (but not necessarily safe or prudent) to enter the intersection after the light turns yellow. Therefore, drivers often accelerate (instead of stopping) when they see a yellow light. This results in cars being in the intersection after the light turns red. It also results in collisions as drivers in the crossing direction enter the intersection in response to a green light. In some intersections, a delay is added so that the crossing light does not become green until sometime after the yellow to red transition. This would seem to be a way to guarantee safety, but it often has the opposite effect. This is because yellow light runners intent on beating the system learn to trust the delay and are even more apt to enter the intersection against a yellow signal. There are also a small number of scofflaws who simply ignore the red signal and stop at nothing (short of a collision).
This problem has been addressed by a growing number of intersections equipped with an automatic camera system that snaps a picture of any car entering the intersection after the signal turns yellow. The photographs are then used to legally fine the offenders with an automatic “photographic citation”. On paper, the system is relatively simple. A sensor in the pavement at the stop line detects the crossing of each automobile. This sensor is linked electronically to the traffic signal timing device. If the signal is red when a car passes over the sensor, this initiates a photography sequence that snaps a picture of the car after a slight delay so that the car is centered in the intersection. There has been considerable controversy over these systems because there is a possibility that the photographed car may not be the same car that tripped the sensor. In addition, the driver has no independent way of proving the status of the light when the vehicle crossed the stop line.